The SilverStripe shop module is a bare-bones product catalog / shopping cart solution.
Add it as a shop component of a website, or use as a full ecommerce website solution.

Customisation is left to the developer, similar to how the SilverStripe CMS is customised.
There is little in the way of online web-interface based configuration, tweaking and setup.
This has been left for the store owner to collaborate with their developer.